>General Running>Social Running App
It looks like Nike has taken down their community/challenges page for the time being. But from what I remember from looking at it years ago, you could create and join communities and see one another's runs on the site. You could also create challenges (so, I could create a 3000 mile/year challenge) and invite people to join them. So, yeah, kinda like what we already do here.
Run the mile you are in.